This invention relates to tufting machines and more particularly to loop pile hook modules.
In a tufting machine a multiplicity of yarn carrying needles penetrate a foundation or backing sheet and loops of yarn are formed therein by loopers which seize the yarn which the loops are shed thereby producing a loop pile article.
As the gauge of tufted products have decreased, i.e. the spacing between adjacent rows of stitches and thus between respective needles and loopers or hooks, modules have been developed wherein the shanks of the respective loopers or hooks are embedded in a common body in side-by-side disposition. Such module looper constructions are illustrated in U.S. Pat. Nos. 4,303,024 and 4,739,717. These modular constructions substantially eliminate the difficulty of aligning hooks or loopers in a respective hook or looper bar of a tufting machine since the hooks or loopers are aligned in a jig during the formation of the module.
A recent trend toward lower pile height carpets has necessitated the development of low profile hooks to enable these products to be manufactured. With conventional hook designs the profile can only be reduced to a limited extent and alternative designs need to be considered to enable ultra low pile height to be achieved.
One difficulty with modular construction is that of replaceability of a broken gauge part, i.e. a hook or looper. If a gauge part breaks, or becomes damaged, the entire module must be removed and replaced. The module being generally discarded. Although possible, in practice partially damaged modules are generally not remanufactured. Thus, it is necessary for these relatively expensive components, i.e. modules, to be discarded prior to the complete exhaustion of their useful economic life. Although damage to loopers is not a common occurrence it can not be entirely eliminated so one alternative is to develop lower cost modular parts to reduce the lost economic value associated with discarding of a module.
Conventional hooks or loopers are made in relatively complex shapes from alloyed steel flat sheet having a body portion comprising a blade and a shank. The shank includes the mounting portion and extends forwardly relative to the blade, i.e. toward backing feed supply rollers. The hooks are disposed in a jig and the body member is cast about the hooks from a material which is commonly used in the art such as low melting point Zinc/lead/aluminum.
The usual arrangement is for the hooks to extend out of the top of the body member with a beak located at the end of the blade and separated from the body member by 20 millimeters or more. With this arrangement, fibers loosened from the yarn are able to lodge between the shanks of adjacent hooks and, if not cleared regularly, accumulate over time to eventually become densely packed and cause problems with the tufting action.
Another disadvantage of the conventional hook design is that the relatively long hook blade is flexible and can be deflected by the needle resulting in poor yarn pick up which in turn can result in an irregular pile surface.
Consequently it is the primary object of the present invention to provide a loop pile hook module for a tufting machine which can be manufactured at relatively low cost and which overcomes the disadvantage identified above.
It is another object of the present invention to provide a loop pile hook module for a tufting machine which can be used to make low pile height fabrics.
It is further object of the present invention to provide a loop pile hook module for a tufting machine which can be used to make fine gauge products.
According to a broadest aspect of the invention there is provided a loop pile hook module for use in a tufting machine, the module has a body member including a plurality of tufting machine hooks therein in side-by-side relationship, the hooks being formed from cylindrical, or other profile, pins which protrude from the body member to form a beak of the hooks.
The body member may be molded, fabricated or otherwise constructed with the hooks cast, mounted or otherwise fixed in a side-by-side relationship therein.
Further aspects of the invention which should be considered in all its novel aspects will become apparent from the following description which is given by way of example only.